We have fepblue BCBS and Medicare part D for my wife. BCBS denied her special medication, and then authorized it for 3 months. She believed BCBS would soon deny the medicine so she signed up for Medicare part D as backup insurance. She called Caremark (CVS) on February 2014 to refill two prescriptions. Surprisingly, only (1) medicine arrived from Aetna home delivery with bill for $41.07 co-payment. Unbeknownst to her, Caremark switched her prescriptions to Aetna home delivery. The local CVS filled the other prescription for $.49. Did CVS violate Medicare rules switching my wife's prescription, and should the secondary insurer BCBS pay $41.07? Thanks for any assistance.